Systems and methods for non-thermal plasma over liquid direct ion injection

ABSTRACT

A system for performing ozone water treatment comprises a voltage supply circuit and a plasma eductor reactor. The voltage supply circuit includes an H-bridge controller and driver, a transformer, and an output port. The H-bridge controller and driver are configured to switch the electrical polarity of a pair of terminals. A primary of the transformer is connected to the H-bridge driver and controller. A secondary of the transformer connects in parallel with a first capacitor and in series with an inductor and a second capacitor. The output port connects in parallel with the second capacitor. The plasma eductor reactor includes an electric field generator, a flow spreader, and a diffuser. The electric field generator includes a pair of electrodes that generate an electric field. The flow spreader supplies a stream of oxygen. The diffuser supplies a stream of water. The streams of water and oxygen pass through the electric field.

BACKGROUND OF THE INVENTION

1. Field of the Invention

Embodiments of the current invention relate to plasma reactors andmethods and systems that utilize plasma reactors.

2. Description of the Related Art

Plasma reactors may include at least two electrodes which are spacedapart. Typically, a voltage difference is applied to the electrodes andan electric field is established between them. A stream of gas may beintroduced to the space between the electrodes such that it passesthrough the electric field. Exposure to the electric field generallyionizes the gas and creates a plasma. If a stream of liquid is alsointroduced to the space between the electrodes, then the plasma may beinjected into the liquid as it passes through the electric field. Plasmainjection into liquid may be utilized for applications such as: in-lineliquid hydrocarbon fuel reforming for hydrogen enrichment to improve thefuel economy of internal combustion engines; nitrogen fixing by directnitrogen ion injection into water; destruction of high molecular weighthydrocarbons (proteins and pharmaceuticals) in drinking water;ammonia/nitrate sequestering for treatment of high nitrate contentwater; demineralization (water softening) for consumer and industrialmarkets; and other similar applications.

SUMMARY OF THE INVENTION

A first embodiment of the current invention provides a plasma eductorreactor comprising a housing, an electric field generator, a flowspreader, and a diffuser. The housing may include an internal reactorchamber. The electric field generator may include a first electrode anda spaced apart second electrode and may generate an electric fieldtherebetween. The first and second electrodes each may have an annularshape of roughly the same size. Together, the first and secondelectrodes may produce a cylindrical electrical field. The plasmaeducator reactor may also include a dielectric element positionedbetween the first and second electrodes, adjacent to the firstelectrode. The flow spreader may supply a stream of gas to the reactorchamber and may be positioned within the reactor chamber concentricallywith the first and second electrodes. The diffuser may supply a streamof liquid to the reactor chamber and may be positioned within thereactor chamber concentrically with the first and second electrodes andthe flow spreader. The stream of liquid and the stream of gas may flowadjacent one another radially outward from the center of the reactorchamber and pass through the electric field.

A second embodiment of the current invention provides a plasma eductorreactor comprising a housing, a liquid passageway, a gas passageway, anelectric field generator, and a diffuser. The housing may include aninternal reactor chamber. The liquid passageway may supply a stream ofliquid to a first end of the reactor chamber. The gas passageway maysupply a stream of gas to the first end of the reactor chamber. Theelectric field generator may include a first electrode and a spacedapart second electrode and may generate an electric field therebetween.The first electrode may have an annular shape, and the second electrodemay have a circular shape with a diameter smaller than an inner diameterof the first electrode such that the second electrode is positionedwithin the interior of the first electrode. The plasma educator reactormay also include a dielectric element positioned between the first andsecond electrodes, adjacent to the first electrode. The diffuser maypossess an elongated cylindrical shape having a circumferential sidewallwith an outer surface. A first end of the diffuser is positioned at thefirst end of the reactor chamber. The stream of liquid flows axiallyaway from the first end of the reactor chamber along the outer surfaceof the sidewall and the stream of gas flows adjacent to the stream ofliquid as both streams pass through the electric field.

A third embodiment of the current invention provides a voltage supplycircuit comprising an H-bridge driver, an H-bridge controller, atransformer, an impedance matching network, an inductor, and an outputport. The H-bridge driver may switch the electrical polarity of a pairof terminals. The H-bridge controller may send a control signal to theH-bridge driver to control the switching of the electrical polarity. Aprimary of the transformer may be connected to the terminals of theH-bridge driver. A secondary of the transformer may be connected inparallel with the impedance matching network. The inductor may beconnected in series with the secondary. The output port may be connectedto the inductor for delivering a voltage to a load.

A fourth embodiment of the current invention provides a voltage supplycircuit comprising a voltage supply circuit comprising a driver, acontroller, a transformer, an impedance matching network, an inductor,and an output port. The driver may switch the electrical polarity of apair of terminals. The controller may send a control signal to thedriver to control the switching of the electrical polarity. A primary ofthe transformer may be connected to the terminals of the driver. Asecondary of the transformer may be connected in parallel with theimpedance matching network. The inductor may be connected in series withthe secondary. The output port may be connected to the inductor fordelivering a voltage to a load.

A fifth embodiment of the current invention provides a system forperforming ozone water treatment. The system may comprise a voltagesupply circuit and a plasma eductor reactor. The voltage supply circuitmay comprise an H-bridge driver, an H-bridge controller, a transformer,a first capacitor, an inductor, a second capacitor, and an output port.The H-bridge driver may switch the electrical polarity of a pair ofterminals. The H-bridge controller may send a control signal to theH-bridge driver to control the switching of the electrical polarity. Aprimary of the transformer may be connected to the terminals of theH-bridge driver. A secondary of the transformer may be connected inparallel with the first capacitor and in series with the inductor andthe second capacitor. The output port may be connected in parallel withthe second capacitor and may deliver a voltage to a load.

The plasma eductor reactor may comprise a housing, an electric fieldgenerator, a flow spreader, and a diffuser. The housing may include aninternal reactor chamber. The electric field generator may include afirst electrode and a spaced apart second electrode and may generate anelectric field therebetween. The first and second electrodes may beconnected to the output port of the voltage supply circuit and each mayhave an annular shape of roughly the same size. Together, the first andsecond electrodes may produce a cylindrical electrical field. The plasmaeducator reactor may also include a dielectric element positionedbetween the first and second electrodes, adjacent to the firstelectrode. The flow spreader may supply a stream of oxygen to thereactor chamber and may be positioned within the reactor chamberconcentrically with the first and second electrodes. The diffuser maysupply a stream of water to the reactor chamber and may be positionedwithin the reactor chamber concentrically with the first and secondelectrodes and the flow spreader. The stream of water and the stream ofoxygen may flow adjacent one another radially outward from the center ofthe reactor chamber and pass through the electric field.

A sixth embodiment of the current invention provides a system forperforming a treatment of a liquid. The system may comprise a voltagesupply circuit and a plasma eductor reactor. The voltage supply circuitmay comprise a driver, a controller, a transformer, a first capacitor,an inductor, a second capacitor, and an output port. The driver mayswitch the electrical polarity of a pair of terminals. The controllermay send a control signal to the driver to control the switching of theelectrical polarity. A primary of the transformer may be connected tothe terminals of the driver. A secondary of the transformer may beconnected in parallel with the first capacitor and in series with theinductor and the second capacitor. The output port may be connected inparallel with the second capacitor and may deliver a voltage to a load.

The plasma eductor reactor may comprise a housing, an electric fieldgenerator, a flow spreader, and a diffuser. The housing may include aninternal reactor chamber. The electric field generator may include afirst electrode and a spaced apart second electrode and may generate anelectric field therebetween. The first and second electrodes may beconnected to the output port of the voltage supply circuit and each mayhave an annular shape of roughly the same size. Together, the first andsecond electrodes may produce a cylindrical electrical field. The plasmaeductor reactor may also include a dielectric element positioned betweenthe first and second electrodes, adjacent to the first electrode. Theflow spreader may supply a stream of gas to the reactor chamber and maybe positioned within the reactor chamber concentrically with the firstand second electrodes. The diffuser may supply a stream of water to thereactor chamber and may be positioned within the reactor chamberconcentrically with the first and second electrodes and the flowspreader. The stream of water and the stream of gas may flow adjacentone another radially outward from the center of the reactor chamber andpass through the electric field.

A seventh embodiment of the current invention provides a method ofcreating a plasma treated liquid. The method comprises the steps ofallowing a liquid to flow into a reactor chamber so as to create a lowpressure area within the reactor chamber adjacent to the flow of theliquid, introducing a gas into the reactor chamber in the low pressurearea to create a gas layer adjacent to the flow of the liquid, exposingthe gas layer to an electric field to ionize the gas and create a layerof plasma above the liquid, and exposing the plasma and the liquid tothe electric field.

This summary is provided to introduce a selection of concepts in asimplified form that are further described below in the detaileddescription. This summary is not intended to identify key features oressential features of the claimed subject matter, nor is it intended tobe used to limit the scope of the claimed subject matter. Other aspectsand advantages of the current invention will be apparent from thefollowing detailed description of the embodiments and the accompanyingdrawing figures.

BRIEF DESCRIPTION OF THE DRAWING FIGURES

Embodiments of the current invention are described in detail below withreference to the attached drawing figures, wherein:

FIG. 1 is an isometric view of a plasma eductor reactor constructed inaccordance with various embodiments of the current invention;

FIG. 2 is a side view of the plasma eductor reactor of FIG. 1;

FIG. 3 is a sectional view of the plasma eductor reactor of FIG. 1 cutalong the line 3-3 of FIG. 2;

FIG. 4 is a sectional view of the plasma eductor reactor of FIG. 1 cutalong the line 4-4 of FIG. 3;

FIG. 5 is a sectional view of the plasma eductor reactor of FIG. 1 cutalong the line 5-5 of FIG. 3;

FIG. 6 is an exploded view of the plasma eductor reactor of FIG. 1;

FIG. 7 is an enlarged view of the sectional view of the plasma eductorreactor from FIG. 4 highlighting an upper portion of a reactor chamber;

FIG. 8 is an isometric view of a second embodiment of the plasma eductorreactor;

FIG. 9 is a sectional view of the plasma eductor reactor of FIG. 8 cutalong the line 9-9 of FIG. 8;

FIG. 10 is a sectional view of the plasma eductor reactor of FIG. 8 cutalong the line 10-10 of FIG. 9;

FIG. 11 is an enlarged view of the sectional view of the plasma eductorreactor from FIG. 9 highlighting an upper portion of a reactor chamber;

FIG. 12 is an exploded view of the plasma eductor reactor of FIG. 8 froman upper perspective;

FIG. 13 is an exploded view of the plasma eductor reactor of FIG. 8 froma lower perspective;

FIG. 14 is a block schematic drawing of a voltage supply circuitconstructed in accordance with various embodiments of the currentinvention;

FIG. 15 is a block schematic drawing of a second embodiment of thevoltage supply circuit;

FIG. 16 is a block schematic drawing of a system for performing ozonewater treatment constructed in accordance with various embodiments ofthe current invention;

FIG. 17 is a flow diagram of a list of steps of a first method forperforming a treatment of a liquid; and

FIG. 18 is a flow diagram of a list of steps of a second method forperforming a treatment of a liquid.

The drawing figures do not limit the current invention to the specificembodiments disclosed and described herein. The drawings are notnecessarily to scale, emphasis instead being placed upon clearlyillustrating the principles of the invention.

DETAILED DESCRIPTION OF THE EMBODIMENTS

The following detailed description of the invention references theaccompanying drawings that illustrate specific embodiments in which theinvention can be practiced. The embodiments are intended to describeaspects of the invention in sufficient detail to enable those skilled inthe art to practice the invention. Other embodiments can be utilized andchanges can be made without departing from the scope of the currentinvention. The following detailed description is, therefore, not to betaken in a limiting sense. The scope of the current invention is definedonly by the appended claims, along with the full scope of equivalents towhich such claims are entitled.

In this description, references to “one embodiment”, “an embodiment”, or“embodiments” mean that the feature or features being referred to areincluded in at least one embodiment of the technology. Separatereferences to “one embodiment”, “an embodiment”, or “embodiments” inthis description do not necessarily refer to the same embodiment and arealso not mutually exclusive unless so stated and/or except as will bereadily apparent to those skilled in the art from the description. Forexample, a feature, structure, act, etc. described in one embodiment mayalso be included in other embodiments, but is not necessarily included.Thus, the current technology can include a variety of combinationsand/or integrations of the embodiments described herein.

Referring to FIGS. 1-7, a plasma eductor reactor 10, constructed inaccordance with at least a first embodiment of the current invention, isshown. The reactor 10 generally receives a gas and a liquid as inputs.The gas may be ionized to form a plasma which is injected into theliquid to create an effluent or product. The plasma eductor reactor 10broadly comprises a housing 12, a top plate 14, a top cap 16, anelectric field generator 18, a dielectric element 20, a flow spreader22, a diffuser 24, a deflector 26, and a reactor chamber 28. The plasmaeductor reactor 10 may also include a plurality of gaskets or seals,such as O-ring seals, that are positioned at the interfaces betweenvarious components of the reactor 10.

Positional and directional terms, such as “upper”, “top”, “lower”,“bottom”, and the like, are used herein to describe various aspects ofthe current invention as shown in the accompanying figures. While thefigures depict the invention in a particular orientation, the inventionmay be utilized in virtually any orientation. The relationship betweenthe components established by the terms still applies when the inventionis utilized in an orientation other than that shown in the figures.

The housing 12 generally retains the components of the plasma eductorreactor 10, and its shape may be adapted to the system in which it isimplemented. The housing may include additional components, such as acollar 30, that adapt the plasma eductor reactor 10 to the system inwhich it is implemented. In some embodiments, the housing may have a boxshape with a plurality of sidewalls. In an exemplary embodiment, thehousing 12 has a generally cylindrical shape with a circumferentialsidewall 32 including an inner surface. The housing 12 may also includecutouts along an outer surface of the sidewall 32 to allow for fastenersto assemble the housing 12 to the top plate 14. In addition, the housing12 may include a gas port 34 and a liquid port 36. The housing 12 may beconstructed from metals, plastics, ceramics, or the like.

The top plate 14 and the top cap 16 generally retain a portion of theelectric field generator 18. The top plate 14 may have a box shape witha plurality of sidewalls and an internal cavity 38 bounded by thesidewalls. The internal cavity 38 may be filled with dielectricmaterials, ceramics, polymers, gases, or the like to provide electricalisolation and suppress undesirable corona discharge from the electricfield generator 18 to the top plate 14. The top cap 16 may be coupled toan upper surface of the top plate 14 and may be roughly disc-shaped witha central opening that contacts the internal cavity 38. The top cap 16may also include an insulator positioned within the central opening.

The electric field generator 18 generates an electric field within thereactor chamber 28 and may include a first electrode 40 and a secondelectrode 42. The electrodes 40, 42 may be spaced apart, and theelectric field may exist between the two electrodes 40, 42. Bothelectrodes 40, 42 may be connected to an external voltage supply whichcontrols the characteristics of the electric field. The voltage supplymay provide a range of approximately 5 kiloVolts (kV) AC toapproximately 25 kV AC with an optional DC offset bias ranging fromapproximately 1 kV to approximately 10 kV. In various embodiments, thefirst electrode 40 may be connected to a variable voltage line, whilethe second electrode 42 may be connected to an electrical ground orneutral. The first electrode 40 may be annular or ring-shaped, althoughother shapes are possible, and may be constructed from a metal, such asiron, nickel, gold, copper, alloys thereof, or the like. The firstelectrode 40 may be located in the internal cavity 38 of the top plate14. The first electrode 40 may also be connected to an electricalconductor 44 that extends to the exterior of the housing 12. Theelectrical conductor 44 may be shaped and sized to fit within theinsulator in the central opening in the top cap 16. The second electrode42 is generally shaped the same as the first electrode 40 and ispositioned to align with the first electrode 40. In some embodiments,the second electrode 42 may be the diffuser 24. In other embodiments,the second electrode 42 may be a diffuser electrode ring 46 positionedwithin the diffuser 24, as described in more detail below. Given theshapes and orientation of the electrodes 40, 42, the electric fieldgenerated may be roughly cylindrical in shape.

The dielectric element 20 generally provides an insulating gap acrosswhich at least a portion of the electric field is established. Thedielectric element 20 may be planar and disc-shaped, although othershapes are possible, and may be constructed from insulating dielectricmaterial such as ceramics, polymers, or the like. An upper surface ofthe dielectric element 20 may be coupled to a lower surface of the topplate 14. In addition, the first electrode 40 may bonded, glued, orotherwise affixed to the upper surface of the dielectric element 20.

The flow spreader 22 generally supplies the gas to the reactor chamber28. The flow spreader 22 may have a generally cylindrical shape with acircumferential sidewall 48 including an inner surface and an outersurface. The hollow interior of the flow spreader 22, bounded by theinner surface of the sidewall 48, may form a gas passageway 50. At afirst end, the flow spreader 22 may include a radially outward extendingflange 52. The outer surface may have a rounded corner between thesidewall 48 and the flange 52. Also at the first end of the flowspreader 22, the inner surface of the sidewall 48 may have afrustoconical cross-sectional shape from which gas exits the gaspassageway 50 and the flow spreader 22. At an opposing second end of theflow spreader 22, gas may enter the gas passageway 50. The flow spreader22 may be positioned opposite the dielectric element 20, such that thereis a small space between the lower surface of the dielectric element 20and a top of the flange 52. The flow spreader 22 may also be positionedconcentrically with the electric field generator 18, such that the outeredge of the flange 52 is within the annular bounds of the first andsecond electrodes 40, 42.

The diffuser 24, in combination with the flow spreader 22, generallyestablishes a radial flow pattern for the liquid before ions areinjected into the liquid. The diffuser 24 may also supply the liquid tothe reactor chamber 28. The diffuser 24 may have a generally cylindricalshape with a circumferential sidewall 54 including an inner surface andan outer surface. The flow spreader 22 may be positioned within thehollow interior of the diffuser 24, such that the flow spreader 22 isconcentric with the diffuser 24. There may a space between the outersurface of the sidewall 48 of the flow spreader 22 and the inner surfaceof the sidewall 54 of the diffuser 24 which forms a liquid passageway56. Accordingly, the liquid passageway 56 may have an annular or ringcross-sectional shape. The top edge of the sidewall 54 may be rounded,arcuate, or curved between the inner surface and the outer surface. Thebottom edge of the sidewall 54 may be coupled to a diffuser cap 58,which closes off one end of the liquid passageway 56, thereby forcingthe liquid in the liquid passageway 56 to flow toward the top edge ofthe sidewall 54. The diffuser 24 may further include one or more liquidinlets 60 in the sidewall 54, near the bottom edge, that supply liquidto the liquid passageway 56.

Furthermore, the combination of the flow spreader 22 and the diffuser 24may create an eductor with educting fluid exiting the eductor at thespace between the flange 52 and the top edge of the diffuser sidewall54. With the educting fluid exiting at a relatively higher flowvelocity, a low pressure area surrounding the opening between the flange52 and the sidewall 54 and adjacent to the flowing fluid is created, asgiven by Bernoulli's principle.

In some embodiments, the diffuser 24 may be constructed fromelectrically conductive materials, such as metals. In such embodiments,the diffuser 24, particularly the top edge of the sidewall 32, may formthe second electrode 42 of the electric field generator 18. In otherembodiments, the diffuser 24 may be constructed from non-conductivematerials, such as plastics or ceramics. With these embodiments, thesecond electrode 42 may be formed by the diffuser electrode ring 46,made from electrically conductive material and positioned within acavity located in the top edge of the sidewall 32 of the diffuser 24.

The deflector 26 generally directs the flow of the plasma and the liquiddownward after the plasma is injected into the liquid. The deflector 26may have an external shape which matches the external shape of thehousing 12. The deflector 26 may be positioned between the housing 12and the top plate 14, such that a lower surface of the deflector 26 maycouple to an upper surface of the housing 12, and an upper surface ofthe deflector 26 may couple to the lower surface of the top plate 14.The deflector 26 may have a hollow interior bounded by an inner surfacewith openings along the upper surface and lower surface of the deflector26. The inner surface may have a curved, arcuate, or roundedcross-sectional shape, such that the inner surface curves outward fromthe lower surface of the deflector 26 to approximately a verticalmidpoint where the inner surface curves inward until the upper surfaceof the deflector 26. The opening along the lower surface of thedeflector 26 may be larger than the opening on the upper surface.Furthermore, the opening on the upper surface of the deflector 26 may becovered by the lower surface of the dielectric element 20.

The reactor chamber 28 generally provides a setting for the gas to beionized and injected into the liquid. The reactor chamber 28 may includean outer surface and an inner surface. The outer surface may be boundedby the lower surface of the dielectric element 20, the inner surface ofthe deflector 26, and the inner surface of the housing 12. The innersurface may be bounded by the outer surface and top edge of the diffuser24 and the first end of the flow spreader 22 including the flange 52.

The plasma eductor reactor 10 may operate as follows. The gas port 34 onthe housing 12 may be coupled to an external gas source, and the liquidport 36 may be coupled to an external pressurized liquid source. The gasmay be supplied at approximately atmospheric pressure or may range up toapproximately 100 pounds per square inch gage (psig). The gas may flowfrom the gas port 34 into the gas passageway 50 of the flow spreader 22.At the first end of the flow spreader 22, the gas may flow from the gaspassageway 50 into the reactor chamber 28. The gas may flow radiallyoutward from the gas passageway 50 in a 360-degree pattern in the spacebetween the flange 52 and the dielectric element 20, thereby creating agas layer. In the vicinity of the outer edge of the flange 52, the gaslayer may encounter a low pressure area created by the flow of theliquid, as described below. As the gas continues to flow, it may passbetween the first electrode 40 and the second electrode 42 and thus,through the electric field established by the electric field generator18. As the gas passes through the electric field, the first electrode 40may discharge which ionizes the gas and converts it into a stream ofplasma with roughly laminar flow.

The characteristics of the electric field may be controlled by theexternal voltage supply which may provide a range of approximately 5kiloVolts (kV) AC to approximately 25 kV AC with an optional DC offsetbias ranging from approximately 1 kV to approximately 10 kV. Thestrength of the electric field is generally the greatest at the shortestdistance between the first electrode 40 and the second electrode 42,which is typically at the peak of the top edge of the sidewall 54 of thediffuser 24 or at the point where the diffuser electrode ring 46 isplaced in the diffuser 24.

The liquid may flow from the liquid port 36 through the liquid inlets 60of the diffuser 24 and into the liquid passageway 56. Given thecurvature of the bottom of the flange 52 and the curvature of the topedge of the diffuser 24, the liquid may exit the liquid passageway 56and flow radially outward in a 360-degree pattern from the eductorstructure of the flow spreader 22 and the diffuser 24 into the reactorchamber 28. The flow of the liquid from the eductor structure may createa low pressure area in the reactor chamber 28 around the outer edge ofthe flange 52. The liquid may then flow through the electric field as astream with roughly laminar flow. The plasma stream may flow on top ofthe liquid stream. As the liquid and the plasma flow through theelectric field, the plasma may be injected into the liquid to create astream of effluent. As the effluent flows outward from the center of thereactor chamber 28, it encounters the inner surface of the deflector 26which directs the effluent stream downward to the bottom of the reactorchamber 28. The effluent may exit the plasma eductor reactor 10 throughthe bottom of the reactor chamber 28.

The use of the flow spreader 22 and the diffuser 24 to create a radialstream of liquid and plasma allows for the use of a planar shapeddielectric element 20, which is easier to manufacture and aligns moreeasily to the liquid stream. The radial flow of the liquid also reducesthe possibility of the liquid bridging the gap between the dielectricelement 20 and the second electrode 42. The radial flow of the liquidmay further create a significant pressure reduction in the gap whichimproves plasma stability, promotes uniformity of the discharge, reducesthe turn-on voltage required for a given operating condition, and allowsfor recirculation of process gas without the addition of externalcompressors or pumps

Referring to FIGS. 8-13, a second embodiment of the plasma eductorreactor 100 may broadly comprise a housing 102, an electric fieldgenerator 104, a dielectric element 106, a nozzle plate 108, a diffuser110, and a reactor chamber 112. The plasma eductor reactor 100 may alsoinclude a plurality of gaskets or seals, such as O-ring seals, that arepositioned at the interfaces between various components of the reactor100.

The housing 102 generally retains the components of the plasma eductorreactor 100 and may include a top plate 114, a spacer plate 116, asupport plate 118, a shell 120, and a bottom plate 122. The top plate114, the spacer plate 116, the support plate 118, and the bottom plate122 may each have a low-profile box shape, each one also having roughlythe same footprint. The shell 120 may have a cylindrical shape. Eachplate 114, 116, 118, 122 may include various through hole, opening, orcutout features. The top plate 114 may include an opening from an uppersurface to a lower surface which serves as a liquid port 126. The spacerplate 116 may include an opening from a side surface to an upper surfacewhich serves as a gas port 128. The support plate 118 may include aninternal cavity 130 centrally located. The support plate 118 may alsohave a circular or ring-shaped feature on its lower surface to receivean upper edge of the shell 120, while the bottom plate 122 may have acircular or ring-shaped feature on its upper surface to receive a loweredge of the shell 120.

The electric field generator 104 is similar to the electric fieldgenerator 18 in function, but is different in terms of architecture. Theelectric field generator 104 may include a first electrode 132 and asecond electrode 134, both of which are connected to the externalvoltage supply, wherein the first electrode 132 may be connected to avariable voltage line, while the second electrode 134 may be connectedto an electrical ground or neutral. The first electrode 132 may beannular or ring-shaped, although other shapes are possible, and may beconstructed from a metal, such as iron, nickel, gold, copper, alloysthereof, or the like. The first electrode 132 may be located in aninternal cavity 136 of the spacer plate 116. The first electrode 132 mayalso be connected to an electrical conductor 137 that extends to theexterior of the housing 102. The electrical conductor 137 may be shapedand sized to fit within an insulator in an opening in the spacer plate116. The second electrode 134 may be the diffuser 110, which ispositioned within and concentric to the first electrode 132.

The dielectric element 106 generally provides an insulating gap acrosswhich at least a portion of the electric field is established. Thedielectric element 106 may have a cylindrical shape with acircumferential sidewall 138 and may be constructed from insulatingdielectric material such as ceramics, polymers, or the like. Thedielectric element 106 may be positioned within the internal cavity 136of the spacer plate 116. The first electrode 132 may be positioned at alower end on an outer surface of the sidewall 138, such that the firstelectrode 132 surrounds, and is concentric with, the dielectric element106.

The nozzle plate 108 generally establishes an axial flow pattern for theliquid and may be roughly disc-shaped with a central opening 140. Thenozzle plate 108 may be positioned between the top plate 114 and thespacer plate 116. An exemplary nozzle plate 108 may include a pluralityof outward extensions from the main disc. The nozzle plate 108 mayfurther include an upper surface and a lower surface. The upper surfacemay include a first cutout impression 142 and a concentric second cutoutimpression 144. The first cutout impression 142 and the second cutoutimpression 144 may each be circular in shape with the second cutoutimpression 144 having a smaller diameter than the first cutoutimpression 142. The lower surface of the top plate 114 may have similarand complementary protruding features. The space between the lowersurface of the top plate 114 and the upper surface of the nozzle plate108 may form a liquid passageway 146. Liquid may flow from the liquidport 126 in the top plate 114 to the first cutout impression 142 and thesecond cutout impression 144 and through the central opening 140. Thelower surface may include a downward extending flange 148 at the centralopening 140. The space between the lower surface of the nozzle plate 108and the upper surface of the spacer plate 116 may form a gas passageway150. Gas may be received from the gas port 128 in the spacer plate 116and may flow along the lower surface toward the flange 148 where the gasis directed downward to the internal cavity 136 of the spacer plate 116.

The diffuser 110 generally establishes an axial flow pattern for theliquid and the gas and may be elongated with a cylindrical shape and acircumferential sidewall 152. Approximately midway along the length ofthe diffuser 110, there may be a bulge, such that the diameter of thesidewall 152 increases and decreases in a roughly sinusoidal fashion.The diffuser 110 may be rigidly retained at an upper end by the topplate 114 and may extend through the internal cavity 130 of the supportplate 118 into the interior of the shell 120. The diffuser 110 may bepositioned in the center of the plasma eductor reactor 100 such that thelongitudinal axis of the diffuser 110 is coaxial with the axis of thereactor 100, and the diffuser 110 is concentric with the dielectricelement 106 and the first electrode 132 of the electric field generator104. In various embodiments, the diffuser 110 may be constructed fromelectrically conductive materials, such as metals, and thus may serve asthe second electrode 134 of the electric field generator 104.

The nozzle plate 108 in combination with the top plate 114 and thediffuser 110 may form an eductor structure, wherein liquid exiting theliquid passageway 146 at the central opening 140 of the nozzle plate 108forms a low pressure area in the reactor chamber 112 adjacent to theliquid.

The reactor chamber 112 generally provides a setting for the gas to beionized and injected into the liquid. The reactor chamber 112 may havean outer surface bounded by the flange 148, the internal cavity 136 ofthe spacer plate 116, an inner surface of the dielectric element 106,the internal cavity of the spacer plate 114, 116, 118, 122, and aninternal surface of the shell 120. The reactor chamber 112 may have aninner surface that includes an outer surface of the diffuser 110.

The plasma eductor reactor 100 may operate as follows. The gas port 128on the housing 102 may be coupled to an external gas source, and theliquid port 126 may be coupled to an external pressurized liquid source.The liquid may flow from the liquid port 126 along the liquid passageway146 including onto the first cutout impression 142 and the second cutoutimpression 144 of the nozzle plate 108 and through the central opening140, which may form the eductor structure. The flow of the liquid out ofthe eductor structure may create a low pressure area in the reactorchamber 112 adjacent to the liquid. The liquid may then flow axiallyalong the entire circumference of the sidewall 152 of the diffuser 110through the internal cavity 136 of the spacer plate 116. The liquid maypass the dielectric element 106 and flow between the first and secondelectrodes 132, 134 and thus, may flow through the electric field.

The gas may flow from the gas port 128 along the gas passageway 150between the upper surface of the spacer plate 116 and the lower surfaceof the nozzle plate 108. The gas may enter the reactor chamber 112 atthe flange 148 of the nozzle plate 108 into the low pressure areacreated by the stream of liquid. The gas may flow axially through thereactor chamber 112 on top of the stream of liquid. Thus, the gas may bepositioned radially outward from the liquid. The gas may pass throughthe electric field while being ionized and converted into a stream ofplasma. The electric field may have similar characteristics to those ofthe plasma eductor reactor 10 and may be at its strongest where thesidewall 152 of the diffuser 110 bulges or curves outward and thedistance between the first and second electrodes 132, 134 is thesmallest. As the liquid and the plasma flow through the electric field,the plasma may be injected into the liquid to create a stream ofeffluent. The effluent may pass through the shell 120 and may exit thereactor chamber 112 through an opening in the bottom plate 122.

Referring to FIG. 14, a voltage supply circuit 200, constructed inaccordance with another embodiment of the current invention, forsupplying voltage to a plasma eductor reactor is shown. The voltagesupply circuit 200 may broadly comprise a base frequency generator 202,a duty cycle generator 204, an auto tune signal generator 206, anH-bridge controller 208, an H-bridge driver 210, a transformer 212, asecondary impedance matching network 214, a gain inductor 216, a ballastcapacitor 218, a phase sensor 220, and an output port 222.

The base frequency generator 202 may include electric or electroniccircuits that generate alternating current (AC), sinusoidal, or periodicelectronic signals comprising voltages and/or currents. The duty cyclegenerator 204 may include electric or electronic circuits thatdetermine, control, or regulate the duty cycle of an electronic signal.The base frequency generator 202 and the duty cycle generator 204 incombination provide the proper timing signals to the H-bridge controller208.

The H-bridge controller 208 may include electric or electronic circuitsthat receive input signals and generate voltages and/or currents thatoperate an H-bridge switching circuit. The H-bridge controller 208 mayreceive inputs from the base frequency generator 202 and the duty cyclegenerator 204. The H-bridge driver 210 may include discrete electricalor electromechanical components that are operable to change the polarityof the voltage and/or the current to an output. The H-bridge driver 210may receive inputs from the H-bridge controller 208 to establish thetiming for switching the polarity of the output.

The transformer 212 may include one or more transformers, as are knownin the art. The transformer 212 may include a primary winding or primary224 and a secondary winding or secondary 226. The primary 224 may beconnected to the H-bridge driver 210. In some embodiments, the voltagesupply circuit 200 may include an optional primary impedance matchingcircuit 228 connected in parallel with the H-bridge driver 210 to matchthe impedance thereof. The secondary impedance matching network 214 mayinclude three terminals 215, 217, 219. A first terminal of the secondary226 may be connected to terminal 215 of the secondary impedance matchingnetwork 214. In some embodiments, the secondary impedance matchingnetwork 214 includes a capacitor in series with an inductor betweenterminals 215 and 219 and a capacitor between terminal 217 and terminal219. In other embodiments, the secondary impedance matching network 214has terminal 215 shorted to terminal 219 and includes a capacitor or acapacitor in series with an inductor connected between terminal 217 andterminals 215, 219. There are other combinations of capacitors andinductors known to those familiar with resonant circuits which canaccomplish this impedance matching function.

A second terminal of the secondary 226 and terminal 217 of the secondaryimpedance matching network 214 may be connected to a ground node 230. Aterminal of the ballast capacitor 218 may be connected to the groundnode 230 through the phase sensor 220. The phase sensor 220 may detectthe phase of the transformer secondary circuit and may communicate thatinformation back to the auto tune signal generator 206.

The output port 222 may be connected in parallel with the ballastcapacitor 218 such that a first terminal 232 is connected to one side ofthe ballast capacitor 218 and a second terminal 234 may be connected tothe ground node 230 through the phase sensor 220. The output port 222may provide an electronic signal, particularly a voltage, to a load. Invarious embodiments, the load may be the plasma eductor reactor 10, 100so that the voltage supply circuit provides the electronic signal to theelectric field generator 18, 104. The first terminal 232 may beconnected to the first electrode 40, 132 and the second terminal 234 maybe connected to the second electrode 42, 134.

The voltage supply circuit 200 may function as follows. The basefrequency generator 202 and the duty cycle generator 204 may providetiming signals to the H-bridge controller 208 which, in turn, providesswitching signals to the H-bridge driver 210. The H-bridge driver 210creates a low-level AC voltage at the primary 224 of transformer 212. Anintermediate-level AC voltage is generated at the secondary 226 andacross the secondary impedance matching network 214, which stores energyfor instantaneous delivery to the gain inductor 216. The AC voltageincreases at the first terminal 232 of the output port 222 due to thegain inductor 216, which has a high Q value. The AC voltage at the firstterminal 232 may also increase as a function of the secondary 226 ACcurrent and the capacitive impedance of the load relative to the secondterminal 234.

In some embodiments, the H-bridge driver 210 is run periodically withoutactually firing the plasma to electrically stimulate any ions to enterthe liquid. During the “on” time, the load (plasma eductor reactor 10,100) may be turned on and off one or many times which has the effect ofincreasing the ionic concentration. The method of using “on” and “off”times this way depends on the process applied.

The voltage supply circuit 200 delivers high voltage AC power to theballast capacitor 218 and the output port 222. In embodiments where thevoltage supply circuit 200 is driving the electric field generator 18,104 of the plasma eductor reactor 10, 100, when the plasma dischargeinitiation voltage is reached the plasma ignites. This happens on everyhalf cycle of the AC wave form. Once ignited, the plasma absorbs energyfrom the voltage supply circuit 200 and the ballast capacitor 218. Theenergy provided by the ballast capacitor 218 increases the plasmaon-time and increases the ion density in the plasma.

The resonant frequency of the voltage supply circuit 200 is largely setby the gain inductor 216 in series with the ballast capacitor 218 whichis in parallel with the load (the plasma eductor reactor 10, 100). Thiscombination is in series with the combination of the transformer 212 andthe secondary impedance matching network 214. In systems, the resonantfrequency is normally dominated by the gain inductor 216 and thecombination of the ballast capacitor 218 and the load (the plasmaeductor reactor 10, 100). Since the voltage supply circuit 200 runs inresonance with impedance matched components, the overall efficiency isimproved over traditional pulse generated plasma drivers and the maximumvoltage generated at the first terminal 232 of the output port 222 isnot limited by the transformer 212 but by the losses in the componentsof the ballast capacitor 218 and the gain inductor 216. By using thegain inductor 216 to increase the voltage, the highest voltage in thevoltage supply circuit 200 is limited to the single node between thegain inductor 216 and the output port 222. The voltage on the remainingcomponents can be limited by careful selection to fractions of the highvoltage node value. For example, for a plasma eductor reactor 10, 100with plasma firing voltage in the range of 8-10 kV, the intermediatevoltage may remain below 600 V and the drive voltage out of the H-bridgedriver 210 is less than 100 V. However there are some applications inwhich a higher Intermediate and drive voltage might be desirable. Thelower operating voltage ahead of the gain inductor 216 allows use of alow cost small, low turn's ratio, lower Q transformer 212 and simplifieddrive electronics resulting in significantly reduced component costs forthe H-bridge driver 210 and matching network while maintaining good,efficient, high frequency performance.

Another advantage of a resonant system of the voltage supply circuit 200is that when low loss components are selected for the ballast capacitor218 and the gain inductor 216, the high voltage will increase (withincertain limits) until the plasma fires and the load begins to absorbenergy. This voltage following feature is very desirable when thephysical characteristics of the gas and/or liquid in the plasma eductorreactor 10, 100 change dynamically during operation. As the pressurechanges or the gas gap thickness changes, the firing voltage changes inresponse. The voltage supply circuit 200 has the capability of followingthis dynamic load in real time. The control of the overvoltage appliedto the plasma eductor reactor 10, 100 can also be tailored to the systemrequirements. The relatively small inductances required in the resonantballast capacitor 218 and gain inductor 216 allow higher frequencyoperation thereof. Since the H-Bridge components operate at much lowervoltage than the ballast capacitor 218 and the gain inductor 216,switching losses are minimized and the operating frequency can be ashigh as practically desired to achieve the plasma densities or powerinput levels required by the plasma eductor reactor 10, 100. In this waycontrol electronics are greatly simplified and cost is reduced. Thisdesign provides both high voltage and high frequency energy to theplasma process in a compact and low cost unit. The high frequencytranslates to high dv/dt (or rapid voltage rate of change) that isconducive to plasma initiation and propagation from the gas into theliquid surface.

The duty cycle generator 204 allows the H-bridge driver 210 to be cycledon and off to customize the plasma on time and off time, as describedabove. This allows power level adjustment independent of the ballastcapacitor 218 and the gain inductor 216 resonant frequency and drivevoltage to optimize the desired plasma characteristics. For instance,optimizing ozone formation in the case of oxygen feed gas involves ashort plasma generating pulse (or pulses) and then a significant plasmaoff time (on the order of 10's of milliseconds) for optimum performance.For example using a 700 kiloHertz (kHz) resonant frequency in theballast capacitor 218 and the gain inductor 216, the H-bridge driver 210can be turned on for 6-12 microseconds (μs) and then turned off for 250μs to allow ozone to form before the next on cycle. This may be modifiedby having the on time include two or more 6-12 μs on times with 4-20 μsrest times followed by a 250 μs off time. In addition, during the offtime the load (the plasma eductor reactor 10, 100) may be stimulated by1-4 μs on times which do not create a plasma but electrically stimulatethe ions in a manner desirable to the process.

The auto-tune function is provided by the phase sensor 220 and auto tunesignal generator 206. This unit allows the H-bridge controller 208 tolock the H-bridge driver 210 switching pulse to the phase of the ballastcapacitor 218 and the gain inductor 216. This is critical for severalreasons. First, the resonant frequency band is very narrow (less than 20Hz in some cases) and is affected by the capacitance of the plasmaeductor reactor 10, 100. This means that changes in the plasma eductorreactor 10, 100 or ambient temperature, the plasma eductor reactor 10,100 gas pressure, and small drift in component characteristics over timecan alter the resonant frequency enough to have significant impact onthe ability of the ballast capacitor 218 and the gain inductor 216 toabsorb energy from the transformer 212. Second, the capacitancefluctuation in within the plasma eductor reactor 10, 100 can occurrapidly leading to very rapid de-tuning and potentially damaging powerreflections. Although the ballast capacitor 218 can mitigate the effectsof this to some degree, to maintain the optimum resonant frequency onevery half cycle, a phase locked system is desirable. The phase sensor220 represents one effective approach to sensing the phase lockingsignal for the phase sensor 220 and auto tune signal generator 206 byemploying a capacitive voltage divider with an optional parallelresistor to detect the phase of the ballast capacitor 218 and the gaininductor 216. This allows the real-time synchronization of H-bridgedriver 210 to the ballast capacitor 218 and the gain inductor 216resonant frequency on each half cycle (twice the operating frequency).As this cycle is less than 1 μs, physical changes in gas pressure,liquid level or other plasma eductor reactor 10, 100 conditions areeffectively tuned out.

Referring to FIG. 15, a second embodiment of the voltage supply circuit300 is shown. The voltage supply circuit 300 is substantially the sameas the voltage supply circuit 200 with the addition of the followingcomponents: a DC power supply 302 and an isolation capacitor 304.

The DC power supply 302 may include one or more direct current (DC)voltage sources as are known, batteries, or combinations thereof. The DCpower supply 302 may be connected between the ground node 230 and thesystem ground potential or earth ground. The isolation capacitor 304 maybe connected in parallel with the DC power supply 302 between the groundnode 230 and system ground.

The voltage supply circuit 300 may operate substantially the same as thevoltage supply circuit 200, except that the DC power supply 302 and theisolation capacitor 304 may vary the voltage of the ground node 230 toabove or below the system ground. This enables the plasma eductorreactor 10, 100 to operate normally and provide a DC bias offset ofeither polarity for aiding the injection of ions into the liquid.

Referring to FIG. 16, a system 400 for performing ozone water treatment,constructed in accordance with various embodiments of the currentinvention is shown. The system 400 may receive untreated raw water, orwater-based liquids, and may inject oxygen radicals and ozone in orderto disinfect the water. The system 400 may broadly comprise a gas inletvalve 402, a water inlet valve 404, a water flow sensor 406, the plasmaeductor reactor 10, 100, the voltage supply circuit 200, 300, a gasseparation unit 408, a gas output valve 410, and a water output valve412. The system 400 may optionally comprise a gas filter 414, a waterfilter 416, and a check valve 418.

The gas inlet valve 402 generally controls the flow of gas coming intothe system 400 and may include gas flow control elements or valves thatare automatically adjusted, actuated, or manually adjusted. The gasinlet valve 402 may receive a supply of oxygen and may provide a streamof oxygen to the plasma eductor reactor 10, 100.

The gas filter 414 generally removes particulates from the oxygen/gasstream from the gas inlet valve 402. The gas filter 414 may include gasor air filtration components as are known. The gas filter 414 may bepositioned in line with the flow of oxygen from the gas inlet valve 402to the plasma eductor reactor 10.

The water inlet valve 404 generally controls the flow of water cominginto the system 400 and may include liquid/fluid flow control elementsor valves that are automatically adjusted, actuated, or manuallyadjusted. The water inlet valve 404 may receive a supply of water andmay provide a stream of water to the water flow sensor 406.

The water filter 416 generally removes particulates from the waterstream from the water inlet valve 404. The water filter 416 may includewater or fluid filtration components as are known. The water filter 416may be positioned in line with the flow of water from the water inletvalve 404 to the water flow sensor 406.

The water flow sensor 406 generally monitors the flow rate of watercoming from the water inlet valve 404 and going to the plasma eductorreactor 10. The water flow sensor 406 may include flow rate sensors,monitors, meters, or the like, as are known in the art. The water flowsensor 406 may be positioned in line with the water inlet valve 404, orthe optional water filter 416, and the plasma eductor reactor 10, 100.

The plasma eductor reactor 10, 100 generally receives the stream ofoxygen and the stream of water and ionizes the oxygen to create a plasmaof oxygen radicals and ozone which is injected into the water in orderto disinfect it. Either embodiment of the plasma eductor reactor 10, 100may be utilized. The stream of oxygen from either the gas inlet valve402 or the gas filter 414 may be coupled to the gas port 34, 128 of theplasma eductor reactor 10, 100. The stream of water from the water flowsensor 406 may be coupled to the liquid port 36, 126 of the plasmaeductor reactor 10, 100.

The voltage supply circuit 200, 300 generally supplies the voltagerequired for the electric field generator 18, 104 of the plasma eductorreactor 10, 100. Either embodiment of the voltage supply circuit 200,300 may be utilized. The output port 222 of the voltage supply circuit200, 300 may be coupled to the electric field generator 18, 104, suchthat the first terminal 232 is connected to the first electrode 40, 132and the second terminal 234 is connected to the second electrode 42,134.

The gas separation unit 408 generally separates the exhaust gas from thetreated water that is output from the plasma eductor reactor 10, 100.The gas separation unit 408 may include a sealed tank of sufficientvolume to handle the output of the plasma eductor reactor 10, 100. Thegas separation unit 408 may also include controls for temperature orother parameters. The gas separation unit 408 may include an effluentinput 420 which receives the treated water from the plasma eductorreactor 10, 100, a gas output 422 located near the top of the tank, anda water output 424 located near the bottom of the tank.

The gas output valve 410 generally controls the flow of gas coming outof the system 400 and may include gas flow control elements or valvesthat are automatically adjusted, actuated, or manually adjusted. The gasoutput valve 410 may receive gas from the gas separation unit 408 andmay allow the gas to vent to the atmosphere. The gas output valve 410may have an optional output that recirculates at least a portion of thegas back to the gas port 34, 128, of the plasma eductor reactor 10, 100.

The check valve 418 generally controls the flow of gas that recirculatesto the plasma eductor reactor 10, 100. The check valve 418 may includegas flow control elements or valves that are unidirectional, or thatallow gas to flow in one direction and not the opposite direction. Thecheck valve 418 may receive gas from the gas output valve 410 and maysupply gas to the gas port 34, 128, of the plasma eductor reactor 10,100.

The system 400 may operate as follows. Oxygen gas may be supplied to thegas inlet valve 402 which delivers the gas either filtered (through thegas filter 414) or unfiltered to the gas port 34, 128 of the plasmaeductor reactor 10, 100. Water, or water-based liquids, from a watertreatment facility or the like, may be supplied to the water inlet valve404 which delivers the water either filtered (through the water filter416) or unfiltered to the liquid port 36, 126. The water may passthrough the water flow sensor 406 which may measure the flow of thewater and send a signal back to the water inlet valve 404 to adjust thewater flow (by opening or closing the valve), if necessary.

The voltage supply circuit 200, 300 may perform as described above andmay supply voltage to the electric field generator 18, 104. The plasmaeductor reactor 10, 100 may receive the oxygen and water and, performingas described above, may ionize the oxygen to create a plasma of oxygenradicals and ozone which is injected into the water. The treated water,or effluent, and the plasma that was not injected exit the plasmaeductor reactor 10, 100. The gas separation unit 408 may receive thetreated water and the plasma and the two may separate, primarily throughthe action of gravity, with the treated water settling on the bottom ofthe gas separation unit 408 and the plasma flowing to the top. Thetreated water may be released into the environment or may undergofurther processing. The plasma may be vented into the atmosphere or atleast a portion of it may be fed back to the gas port 34, 128 to providethe source gas for the plasma eductor reactor 10, 100.

The system 400 described herein provides the following features andadvantages. When utilized for water treatment or water purification, thesystem 400 generates short-lived but highly active oxygen radicals thatare extremely reactive and capable of rapidly damaging cell membranes aswell as proteins and/or lipids in viruses. The system 400 also generateslonger lived ozone molecules that attack organics and damages cellmembranes and have a more lasting effect. The exposure of the water filmto the very high electric field (on the order of 50,000V/cm) in theplasma eductor reactor 10, 100 enables an electro-poration mechanism todamage cell walls of microbes passing through it via the liquid and aidsin sterilization. This can happen with or without the plasma beingenergized. In addition, the expansion of the gas when the plasma isenergized creates high intensity ultrasonic energy in the gas which isdirectly coupled to the liquid and is intense enough to enableultrasonic lysing of cell membranes. Since the pulse rise times are veryshort, sound travels through liquid very well, the layer is very thin,and the sonic energy wave in the liquid is significant throughout thelayer and will aid destruction of cellular bodies. Furthermore, theability of the system 400 to modify the high voltage pulses in such away as to accentuate one or more of these features allows some degree oftailoring the process to a particular need, such as enhancing onetreatment or purification mechanism vs. another.

At least a portion of the steps of a first method 500 for performing atreatment of a liquid in accordance with various embodiments of thepresent invention is listed in FIG. 17. The steps may be performed inthe order as shown in FIG. 17, or they may be performed in a differentorder. Furthermore, some steps may be performed concurrently as opposedto sequentially. In addition, some steps may be omitted.

Referring to step 501, a gas is introduced to a plasma eductor reactor10 that includes a reactor chamber 28. The plasma eductor reactor 10 mayalso include a gas port 34 and a gas passageway 50 that couples with thereactor chamber 28.

Referring to step 502, a liquid is introduced to the plasma eductorreactor 10. The plasma eductor reactor 10 may also include a liquid port36 and a liquid passageway 56 that couples with the reactor chamber 28.

Referring to step 503, the liquid is force to flow radially outward froma central axis of the reactor chamber 28 to create a stream of liquid.The plasma eductor reactor 10 may include a cylindrical flow spreader 22positioned within a cylindrical diffuser 24 forming the liquidpassageway 56 therebetween. The flow spreader 22 may include an outwardextending flange 52 which forces the radial flow of the liquid.

Referring to step 504, the gas is forced to flow radially outward fromthe central axis to create a layer of gas adjacent to the stream ofliquid. The flow spreader 22 may include a hollow interior shaft whichforms the gas passageway 50. The opening of the gas passageway may bepositioned in proximity to a planar dielectric element 20 which helpsprovide radial flow of the gas.

Referring to step 505, an electric field with a roughly cylindricalshape is applied to the layer of gas and the stream of liquid. Theelectric field may be applied with an electric field generator 18including a first electrode 40 and a spaced apart second electrode 42,both of which may possess a roughly annular shape. The first electrode40 may be positioned on one side of the dielectric element 20, while thesecond electrode 42 may be positioned within the reactor chamber 28. Avoltage may be applied to the first electrode 40 and the secondelectrode 42. The voltage may have a range of approximately 5 kiloVolts(kV) AC to approximately 25 kV AC with an optional DC offset biasranging from approximately 1 kV to approximately 10 kV.

Application of the electric field to the gas may ionize the gas tocreate a plasma. A portion of the plasma may be injected into the liquidunder the influence of the electric field.

Referring to step 506, the gas and the liquid are allowed to exit thereactor chamber 28 and enter a gas separation unit 408. The gasseparation unit 408 may include a tank with an internal chamber whichreceives the liquid and the gas.

Referring to step 507, the liquid is drained from the gas separationunit 408. The gas separation unit 408 may be coupled to a water outputvalve 412, through which the liquid flows.

Referring to step 508, the gas is directed from the gas separation unit408 to the plasma eductor reactor 10. The gas separation unit 408 may becoupled to a gas output valve 410 which is connected to the gas port 34of the plasma eductor reactor 10.

At least a portion of the steps of a second method 600 for performing atreatment of a liquid in accordance with various embodiments of thepresent invention is listed in FIG. 18. The steps may be performed inthe order as shown in FIG. 18, or they may be performed in a differentorder. Furthermore, some steps may be performed concurrently as opposedto sequentially. In addition, some steps may be omitted.

Referring to step 601, a gas is introduced to a plasma eductor reactor100 that includes a reactor chamber 112. The plasma eductor reactor 100may also include a gas port 128 and a gas passageway 150 that coupleswith the reactor chamber 112.

Referring to step 602, a liquid is introduced to the plasma eductorreactor 100. The plasma eductor reactor 100 may also include a liquidport 126 and a liquid passageway 146 that couples with the reactorchamber 112.

Referring to step 603, the liquid is force to flow axially from a firstend of the reactor chamber 112 along an outer surface of a diffuser 110to create a stream of liquid. The plasma eductor reactor 100 may includea nozzle plate 108 with an upper surface that forms a portion of theliquid passageway 146. The nozzle plate 108 may include a centralopening 140 which surrounds the diffuser 110. After it flows through theopening 140, the stream of liquid may surround the outer surface of thediffuser 110.

Referring to step 604, the gas is forced to flow axially from the firstend of the reactor chamber 112 to create a layer of gas adjacent to thestream of liquid. The nozzle plate 108 may include a lower surface whichforms a portion of the gas passageway 150. The gas may enter the reactorchamber 112 and flow axially above the stream of liquid.

Referring to step 605, an electric field is applied to the layer of gasand the stream of liquid. The electric field may be applied with anelectric field generator 104 including a first electrode 132 with aroughly annular shape and a spaced apart second electrode 134. The firstelectrode 132 may be positioned on one side of a dielectric element 106with a cylindrical shape that surrounds a portion of the reactor chamber112 and the diffuser 110 therein. The second electrode 134 may be a partof or positioned within the diffuser 110. A voltage may be applied tothe first electrode 132 and the second electrode 134. The voltage mayhave a range of approximately 5 kiloVolts (kV) AC to approximately 25 kVAC with an optional DC offset bias ranging from approximately 1 kV toapproximately 10 kV.

Application of the electric field to the gas may ionize the gas tocreate a plasma. A portion of the plasma may be injected into the liquidunder the influence of the electric field.

Referring to step 606, the gas and the liquid are allowed to exit thereactor chamber 112 and enter a gas separation unit 408. The gasseparation unit 408 may include a tank with an internal chamber whichreceives the liquid and the gas.

Referring to step 607, the liquid is drained from the gas separationunit 408. The gas separation unit 408 may be coupled to a water outputvalve 412, through which the liquid flows.

Referring to step 608, the gas is directed from the gas separation unit408 to the plasma eductor reactor 100. The gas separation unit 408 maybe coupled to a gas output valve 410 which is connected to the gas port128 of the plasma eductor reactor 100.

Although the invention has been described with reference to theembodiments illustrated in the attached drawing figures, it is notedthat equivalents may be employed and substitutions made herein withoutdeparting from the scope of the invention as recited in the claims.

Having thus described various embodiments of the invention, what isclaimed as new and desired to be protected by Letters Patent includesthe following:
 1. A plasma eductor reactor comprising: a housingincluding a reactor chamber internal to the housing; an electric fieldgenerator including a first electrode and a spaced apart secondelectrode configured to generate an electric field therebetween, thefirst and second electrodes each having an annular shape of roughly thesame size and together producing a cylindrical electrical field; a flowspreader to supply a stream of gas to the reactor chamber, the flowspreader positioned within the reactor chamber concentrically with thefirst and second electrodes; and a diffuser to supply a stream of liquidto the reactor chamber, the diffuser positioned within the reactorchamber concentrically with the first and second electrodes and the flowspreader, wherein the stream of liquid and the stream of gas flowadjacent one another radially outward from the center of the reactorchamber and pass through the electric field.
 2. The plasma eductorreactor of claim 1, further comprising a dielectric element planar inshape with a first surface and an opposing second surface and positionedat a top of the reactor chamber, wherein the first electrode is coupledto the first surface and the second electrode is spaced apart from thesecond surface.
 3. The plasma eductor reactor of claim 1, wherein theflow spreader is cylindrical in shape with a circumferential sidewalland an outward extending flange at one end thereof, wherein the streamof gas flows along the interior of the sidewall.
 4. The plasma eductorreactor of claim 3, wherein the diffuser is cylindrical in shape with acircumferential sidewall such that the sidewall of the flow spreader ispositioned within the sidewall of the diffuser and the stream of liquidflows between the two sidewalls.
 5. The plasma eductor reactor of claim1, further comprising a deflector encircling the flow spreader and thediffuser to direct the streams of gas and liquid downward to exit thereactor chamber.
 6. The plasma eductor reactor of claim 1, wherein theelectric field generator ionizes the gas to create a plasma adjacent tothe liquid.
 7. The plasma eductor reactor of claim 6, wherein theeffluent and the plasma exit the chamber at a bottom of the reactorchamber away from the flow spreader and the diffuser.
 8. A plasmaeductor reactor comprising: a housing including a reactor chamberinternal to the housing; a liquid passageway to supply a stream ofliquid to a first end of the reactor chamber; a gas passageway to supplya stream of gas to the first end of the reactor chamber; an electricfield generator including a first electrode and a spaced apart secondelectrode configured to generate an electric field therebetween, thefirst electrode having an annular shape and the second electrode havinga circular shape with a diameter smaller than an inner diameter of thefirst electrode such that the second electrode is positioned within theinterior of the first electrode; and a diffuser of elongated cylindricalshape having a circumferential sidewall with an outer surface, a firstend of the diffuser positioned at the first end of the reactor chamber,wherein the stream of liquid flows axially away from the first end ofthe reactor chamber along the outer surface of the sidewall and thestream of gas flows adjacent to the stream of liquid as both streamspass through the electric field.
 9. The plasma eductor reactor of claim8, further comprising a dielectric element cylindrical in shape having acircumferential sidewall with an outer surface, wherein the dielectricelement is positioned such that the sidewall of the dielectric elementsurrounds the sidewall of the diffuser and the first electrode ispositioned along the outer surface of the dielectric element sidewall.10. The plasma eductor reactor of claim 8, wherein the diffuser includesthe second electrode.
 11. The plasma eductor reactor of claim 8, whereinthe diffuser sidewall includes an outward extending curvature located inalignment with the first electrode.
 12. The plasma eductor reactor ofclaim 8, wherein the electric field generator ionizes the gas to createa plasma, at least a portion of which is injected into the liquid tocreate an effluent.
 13. A voltage supply circuit comprising: an H-bridgedriver configured to switch the electrical polarity of a pair ofterminals; an H-bridge controller configured to send a control signal tothe H-bridge driver to control the switching of the electrical polarity;a transformer including a primary connected to the terminals of theH-bridge driver and a secondary; an impedance matching network connectedin parallel with the secondary; an inductor connected in series with thesecondary; and an output port connected to the inductor for delivering avoltage to a load.
 14. The voltage supply circuit of claim 13, furthercomprising a duty cycle generator configured to send a signal to theH-bridge controller to set the duty cycle of the control signal.
 15. Thevoltage supply circuit of claim 13, further comprising a base frequencygenerator configured to send a signal to the H-bridge controller to setthe frequency of the control signal.
 16. The voltage supply circuit ofclaim 13, wherein the impedance matching network includes a capacitor.17. The voltage supply circuit of claim 16, wherein the impedancematching network includes an inductor in series with the capacitor. 18.The voltage supply circuit of claim 13, further comprising a firstcapacitor connected in series with the secondary and in parallel withthe output port.
 19. The voltage supply circuit of claim 18, furthercomprising a phase sensor to sense a phase of current through the loadand the first capacitor and an auto tune signal generator configured tosend a signal to the H-bridge controller to set a phase value of thecontrol signal to adjust the phase of the H-bridge driver to approximatea resonant frequency of the secondary.
 20. A voltage supply circuitcomprising: a driver configured to switch the electrical polarity of apair of terminals; a controller configured to send a control signal tothe driver to control the switching of the electrical polarity; atransformer including a primary connected to the terminals of the driverand a secondary; an impedance matching network connected in parallelwith the secondary; an inductor connected in series with the secondary;and an output port connected to the inductor for delivering a voltage toa load.
 21. The voltage supply circuit of claim 20, wherein the driveris an H-bridge driver and the controller is an H-bridge controller. 22.The voltage supply circuit of claim 20, further comprising a duty cyclegenerator configured to send a signal to the controller to set the dutycycle of the control signal.
 23. The voltage supply circuit of claim 20,further comprising a base frequency generator configured to send asignal to the controller to set the frequency of the control signal. 24.The voltage supply circuit of claim 20, wherein the impedance matchingnetwork includes a capacitor.
 25. The voltage supply circuit of claim24, wherein the impedance matching network includes an inductor inseries with the capacitor.
 26. The voltage supply circuit of claim 20,further comprising a first capacitor connected in series with thesecondary and in parallel with the output port.
 27. The voltage supplycircuit of claim 20, further comprising a phase sensor to sense a phaseof current through the load and the first capacitor and an auto tunesignal generator configured to send a signal to the controller to set aphase value of the control signal to adjust the phase of the driver toapproximate a resonant frequency of the secondary.
 28. A system forperforming ozone treatment, the system comprising: a voltage supplycircuit including: an H-bridge driver configured to switch theelectrical polarity of a pair of terminals, an H-bridge controllerconfigured to send a control signal to the H-bridge driver to controlthe switching of the electrical polarity, a transformer including aprimary connected to the terminals of the H-bridge driver and asecondary, an impedance matching network connected in parallel with thesecondary, an inductor connected in series with the secondary, an outputport connected to at least one terminal of the secondary for deliveringa voltage to a load, and a phase sensor to sense a phase of currentthrough components connected to the secondary and an auto tune signalgenerator configured to send a signal to the H-bridge controller to seta phase value of the control signal to adjust the phase of the H-bridgedriver to approximate a resonant frequency of the secondary; and aplasma eductor reactor including: a housing including a reactor chamberinternal to the housing, an electric field generator including a firstelectrode and a spaced apart second electrode configured to generate anelectric field therebetween, the first and second electrodes connectedto the output port of the voltage supply circuit, each having an annularshape of roughly the same size and together producing a cylindricalelectrical field, a flow spreader to supply a stream of oxygen to thereactor chamber, the flow spreader positioned within the reactor chamberconcentrically with the first and second electrodes, and a diffuser tosupply a stream of liquid to the reactor chamber, the diffuserpositioned within the reactor chamber concentrically with the first andsecond electrodes and the flow spreader, wherein the stream of liquidand the stream of oxygen flow adjacent one another radially outward fromthe center of the reactor chamber and pass through the electric field.29. The system of claim 28, wherein the electric field generator ionizesthe oxygen to create a plasma of oxygen radicals and ozone that existadjacent to the liquid.
 30. The system of claim 29, further comprising agas separation unit to receive the treated liquid and the plasma fromthe plasma eductor reactor and to separate the plasma from the liquidsuch that the liquid may exit the system and at least a portion of theplasma may be recirculated to the plasma eductor reactor.
 31. The systemof claim 28, wherein the flow spreader is cylindrical in shape with afirst circumferential sidewall and an outward extending flange at oneend thereof, such that the stream of gas flows along the interior of thesidewall and the diffuser is cylindrical in shape with a secondcircumferential sidewall such that the first sidewall is positionedwithin the second sidewall and the stream of liquid flows between thetwo sidewalls.
 32. The voltage supply circuit of claim 28, wherein theimpedance matching network includes a capacitor.
 33. The voltage supplycircuit of claim 32, wherein the impedance matching network includes aninductor in series with the capacitor.
 34. A system for performing atreatment of a liquid, the system comprising: a voltage supply circuitincluding: a driver configured to switch the electrical polarity of apair of terminals, a controller configured to send a control signal tothe driver to control the switching of the electrical polarity, atransformer including a primary connected to the terminals of the driverand a secondary, an impedance matching network connected in parallelwith the secondary, an inductor connected in series with the secondary,an output port connected to at least one terminal of the secondary fordelivering a voltage to a load, and a phase sensor to sense a phase ofcurrent through components connected to the secondary and an auto tunesignal generator configured to send a signal to the controller to set aphase value of the control signal to adjust the phase of the driver toapproximate a resonant frequency of the secondary; and a plasma eductorreactor including: a housing including a reactor chamber internal to thehousing, an electric field generator including a first electrode and aspaced apart second electrode configured to generate an electric fieldtherebetween, the first and second electrodes connected to the outputport of the voltage supply circuit, each having an annular shape ofroughly the same size and together producing a cylindrical electricalfield, a flow spreader to supply a stream of gas to the reactor chamber,the flow spreader positioned within the reactor chamber concentricallywith the first and second electrodes, and a diffuser to supply a streamof liquid to the reactor chamber, the diffuser positioned within thereactor chamber concentrically with the first and second electrodes andthe flow spreader, wherein the stream of liquid and the stream of gasflow adjacent one another radially outward from the center of thereactor chamber and pass through the electric field.
 35. The system ofclaim 34, wherein the electric field generator ionizes the gas to createa plasma that exists adjacent to the liquid.
 36. The system of claim 35,further comprising a gas separation unit to receive the treated liquidand the plasma from the plasma eductor reactor and to separate theplasma from the liquid such that the liquid may exit the system and atleast a portion of the plasma may be recirculated to the plasma eductorreactor.
 37. The system of claim 34, wherein the flow spreader iscylindrical in shape with a first circumferential sidewall and anoutward extending flange at one end thereof, such that the stream of gasflows along the interior of the sidewall and the diffuser is cylindricalin shape with a second circumferential sidewall such that the firstsidewall is positioned within the second sidewall and the stream ofliquid flows between the two sidewalls.
 38. The voltage supply circuitof claim 34, wherein the impedance matching network includes acapacitor.
 39. The voltage supply circuit of claim 38, wherein theimpedance matching network includes an inductor in series with thecapacitor.
 40. A method of creating a plasma treated liquid, the methodcomprising the steps of: allowing a liquid to flow into a reactorchamber so as to create a low pressure area within the reactor chamberadjacent to the flow of the liquid; introducing a gas into the reactorchamber in the low pressure area to create a gas layer adjacent to theflow of the liquid; exposing the gas layer to an electric field toionize the gas and create a layer of plasma above the liquid; andexposing the plasma and the liquid to the electric field.
 41. The methodof claim 40, further comprising the steps of allowing the gas, theplasma, and the liquid to exit the reactor chamber and enter a gasseparation unit; draining the liquid from the gas separation unit; anddirecting the gas from the gas separation unit to reenter the reactorchamber.